How do I Winterize my Yamaha Outboard Motor?

  • Run out of as much old fuel as possible before discontinuing use for the season, then fill the tank with fresh fuel treated with the appropriate amount of Yamalube Ring Free Plus and Yamalube Fuel Stabilizer & Conditioner Plus.  This helps minimize the possibility of moisture being absorbed in the fuel from the air, and ensures that treated fuel will reach all parts of the engine's fuel system.
  • Four stroke models: change the oil and filter.
  • Change all the fuel filters on the motor plus the boat mounted 10 micron fuel/water separator filter.
  • Remove the propeller and check for fishing line.  Do not reinstall until after the motor has been run for the final time.  Remember to grease the propshaft splines before reinstalling the propeller.
  • Remove the lower unit and inspect/change the water pump impeller for its yearly or 100 hour service.  Be sure to lube the driveshaft splines and bushings before reinstalling the lower unit.
  • Change the gearcase lube.
    • Inspect the lube for the presence of water.  If water is present, this is a good time to line up some off-season work.
    • Replace both fill and drain plug washers.
  • Two stroke models: fill the PBS oil tank with Yamalube 2M oil.  This will help prevent the formation of condensation.
  • Run the engine on a flushing device, using fresh water, for at least 10-15 minutes to flush salt residue, sand, and mud from the cooling passages plus to allow treated fuel to circulate through the whole fuel system.
  • Fog the engine
    • Single throttle body motors: mix one quart of Yamalube EFI Storage Fogging Oil to 2 gallons of fuel in a portable fuel tank.  Connect the portable tank to the motors quick-connect fitting (F4-F70) or to the inlet of the primary fuel filter on larger models.  Run the motor at a fast idle for 10-15 minutes.  Smoke from the fogging oil should be visible in the exhaust.
    • Multiple carbor throttle valve motors: just prior to turning the engine OFF during flushing, spray Yamalube Stor-Rite Engine Fogging Oil into each throttle bore, until the engine almost stalls.
    • All motors: remove the spark plugs and spray Yamalube Stor-Rite Enging Fogging Oil into each cylinder for a few seconds.  Turn/crank the engine over with the engine stop switch lanyard.  Remove to distirbute the fogging oil over the cylinder walls and valves.  Reinstall and tighten the spark plugs to the specified torque value.
  • Shut off or disconnect the main fuel supply.  Drain the vapor separator tank (VST) or carburetors.  You may have to disconnect the VST vent line or depress the vent valve on models equipped with a vapor shut off valve to break the vaccuum allowing the fuel to drain.
  • Wash off the exterior of the engine with fresh water and dry completelyNote: Do not spray the motor while it is running.
  • Spray the powerhead and rubber components with Yamalube Silicone Protectant & Lubricant or Yamashield.
  • Wax the top cowling with non-abrasive wax.
  • Grease all zerk fittings and linkages on the motor as well as the steering mechanism using Yamalube Marine Grease.
  • Trim the motor as far down as possible to allow any water remaining in the powerhead or exhaust passages to completely drain out before tilting the motor up for transport or storage.
  • Disconnect and remove the battery from the boat.  Clean the battery casing, terminals, and battery cable ends and spray with Yamalube Battery Terminal Cleaner & Protector.  Fill each cell to the proper level with distilled water.
  • Cover the engine console/gauges.